1. Field of the Invention
This invention relates to curculin C (one of curculin homologue) having a stable and potent taste-modification effect, which is obtained from Curculigo latifolia.
2. Description of the Prior Art
The present inventors formerly found out a substance serving as a taste-modifier, which was named "curculin (curculin homologue, hereinafter referred to as curculin)" by them, from Curculigo latifolia fruits growing in Western Malaysia and the southern part of Thailand and belonging to the genus Curculigo of the family Hypoxidaceae or Amaryllidaceae. Further, they found out that this curculin was a protein and that a sour material or water taken after eating it would taste sweet, and applied for a patent based on these findings (refer to Japanese- Patent Laid-Open No. 104263/1990.) Subsequently, they succeeded in highly purifying this protein curculin (one of curculin homologue, hereinafter referred to as curculin A) and applied for a patent on a taste-modifier having the amino acid sequence thereof (refer to Japanese Patent Laid-Open No. 190899/1991).
In spite of the accomplishment of these inventions, however, it has been desired to develop a substance having a more stable and potent taste-modification activity.